Bzip2 Compression Functions

Introduction

The bzip2 functions are used to transparently read and write bzip2 (.bz2) compressed files.

Requirements

This module uses the functions of the » bzip2 library by Julian Seward. This module requires bzip2/libbzip2 version >= 1.0.x.

Installation

Bzip2 support in PHP is not enabled by default. You will need to use the --with-bz2[=DIR] configuration option when compiling PHP to enable bzip2 support.

Runtime Configuration

This extension has no configuration directives defined in php.ini.

Resource Types

This extension defines one resource type: a file pointer identifying the bz2-file to work on.

Predefined Constants

This extension has no constants defined.

Examples

This example opens a temporary file and writes a test string to it, then prints out the contents of the file.

Example 357. Small bzip2 Example

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<?php


$filename = "/tmp/testfile.bz2";
$str = "This is a test string.\n";

// open file for writing
$bz = bzopen($filename, "w");

// write string to file
bzwrite($bz, $str);

// close file
bzclose($bz);

// open file for reading
$bz = bzopen($filename, "r");

// read 10 characters
echo bzread($bz, 10);

// output until end of the file (or the next 1024 char) and close it.  
echo bzread($bz);

bzclose($bz);

?>

Table of Contents

bzclose — Close a bzip2 file
bzcompress — Compress a string into bzip2 encoded data
bzdecompress — Decompresses bzip2 encoded data
bzerrno — Returns a bzip2 error number
bzerror — Returns the bzip2 error number and error string in an array
bzerrstr — Returns a bzip2 error string
bzflush — Force a write of all buffered data
bzopen — Opens a bzip2 compressed file
bzread — Binary safe bzip2 file read
bzwrite — Binary safe bzip2 file write

Code Examples / Notes » ref.bzip2

ec10

<?php /** * @return bool * @param string $in * @param string $out * @desc compressing the file with the bzip2-extension */ function bzip2 ($in, $out) { if (!file_exists ($in) || !is_readable ($in)) return false; if ((!file_exists ($out) && !is_writeable (dirname ($out)) || (file_exists($out) && !is_writable($out)) )) return false; $in_file = fopen ($in, "rb"); $out_file = bzopen ($out, "wb"); while (!feof ($in_file)) { $buffer = fgets ($in_file, 4096); bzwrite ($out_file, $buffer, 4096); } fclose ($in_file); bzclose ($out_file); return true; } /** * @return bool * @param string $in * @param string $out * @desc uncompressing the file with the bzip2-extension */ function bunzip2 ($in, $out) { if (!file_exists ($in) || !is_readable ($in)) return false; if ((!file_exists ($out) && !is_writeable (dirname ($out)) || (file_exists($out) && !is_writable($out)) )) return false; $in_file = bzopen ($in, "rb"); $out_file = fopen ($out, "wb"); while ($buffer = bzread ($in_file, 4096)) { fwrite ($out_file, $buffer, 4096); } bzclose ($in_file); fclose ($out_file); return true; } ?>